Sand is becoming New England coastal dwellers’ most coveted and controversial commodity as they try to fortify beaches against rising seas and severe erosion caused by violent storms.

From Rhode Island to Maine, debates over who gets sand, who pays for it, and where it comes from are fast becoming some of the region’s most contentious oceanfront issues. In many cases, taxpayers are being asked to foot some of the bill for beach-rebuilding projects.

“It’s called the sand wars,’’ said S. Jeffress Williams, a coastal geologist and scientist emeritus with the United States Geological Survey in Woods Hole and the University of Hawaii. The disputes, happening across the coastal United States, “are only going to get more intense,” he said.

Among the seaside squabbles, some residents in Salisbury want $300,000 in state taxpayer dollars for sand to help protect private homes from the ocean’s fury.

The public Winthrop Beach is poised to receive an estimated 20,000 truckloads of sand from Saugus as part of a massive beach replenishment and improvement project that is costing state taxpayers $26 million.

John Tlumacki/Globe Staff/File

Beach sand was used to form a makeshift berm at Yirrell Beach in Winthrop to protect oceanfront homes in advance of a Nor'easter eariler this year.

And in ocean-battered Nantucket and Plum Island, residents want to pay privately for sand to stand sentry against the encroaching ocean — but are running into regulators’ opposition over how best to protect property.

For all the billions of grains of silica on and off New England’s coastline, sand is maddeningly difficult — and expensive — to get. Fishermen and their regulators have opposed the mining of offshore sand because they worry it will harm sea life. Environmental officials say bulldozing it across beaches can accelerate erosion and harm bird nesting grounds. Mining and trucking sand from inland sources to beaches can be more than four times as expensive, damage roads, and produce sand that is often darker and a different texture.

‘If we want to have beaches in Massachusetts we have to sustain them — it’s just like painting a bridge.’

Meanwhile, the availability of large amounts of sand that once was deposited onto area beaches as a byproduct of federal navigational dredging is declining, along with funding for those projects.

The stakes are rising with sea levels. New England seas are rising at an annual rate three to four times faster than the global average. Scientists predict that the ocean here could rise 3 feet by the end of the century and that this region could see more powerful storms like those in 2011 and 2012 because of climate change. The one-two punch of powerful storm surges atop higher seas is expected to mean more erosion and flooding — reaching farther inland.

Replenishing beaches is big business elsewhere along the Atlantic Coast, where long meandering ribbons of sand from New York to Florida have been fortified for decades, using taxpayer dollars to protect shorefront homes and vacation destinations. New England beaches tend to be smaller and much of the coast is privately owned, so big projects never gained much political traction. There is also, environmentalists say, a leftover suspicion of mining anything from the sea that stretches back to oil exploration attempts in the early 1980s.

But as officials frown upon the construction of new seawalls because it can exacerbate erosion, sand is becoming increasingly valuable as the first line of defense against the ocean.

Recordkeeping is poor on New England sand replenishment, and costs are often shared among multiple government and even private entities. Massachusetts, however, has begun to develop a database to track the use of sand. Using that database and in interviews with coastal communities, the New England Center for Investigative Reporting conservatively estimates more than $40 million in federal, state, and local funds have been spent to place sand on Massachusetts’ public beaches in the past 10 years.

That amount is minuscule compared with the billions being spent to protect and replenish beaches farther south in the wake of Hurricane Sandy — yet coastal specialists say demand for sand is guaranteed to rise for public and private beaches.

Massachusetts is now reexamining the possibility of mining sand offshore, and a special commission on coastal erosion has been established by the state Legislature.

Many coastal dwellers and communities argue that the state and federal governments need to take care of beaches much the way they maintain roads. But others, often those farther away, say constantly replenishing beaches, many in front of second homes, with taxpayer dollars is a losing proposition.

“I don’t think taxpayers have any idea what they are paying for,’’ said Peter Shelley, senior counsel for the Conservation Law Foundation, a legal advocacy group. He said public dollars are needed to protect Boston’s infrastructure to ensure the region’s economic hub is protected, not “people’s beach houses. These beach replenishment projects are temporary at best.”

The hunt for sand

The idea seemed simple more than a decade ago: Mine gravel and sand some 8 miles off Winthrop’s storm-battered beach and place it in front of a sea wall to act as the town’s first defense against powerful waves.

But fishermen and their federal regulators opposed the sand mining, saying it would disturb essential habitat for cod. After years of controversy, it was decided that trucks would bring in the sand from an abandoned highway project in Saugus. The price tag is close to three times the original estimate.

The project — one of the longest and most controversial in the state involving sand replenishment — has had a chilling effect, coastal community officials and engineers say.

Pat Greenhouse/Globe Staff/File

Work on a Plum Island and Salisbury Beach renourishment project continued in this October 2010 photo.

“Massachusetts is one of the most restrictive states for sand mining,’’ said John Ramsey, coastal engineer and co-owner of Applied Coastal Research and Engineering in Mashpee, which works with coastal communities on the Atlantic and Gulf coasts. He said fishing interests have prevented the conversation here, but elsewhere “sand mining is accepted — and encouraged — as a method of shore protection.”

Massachusetts has permitted only a few private and public projects to take sand from offshore for beach replenishment, according to a review of dozens of projects. Orleans officials, for example, are allowed to take sand each year from flats about 500 feet from Skaket Beach.

Yet the rising demand for sand has the state reexamining offshore mining. The state is updating its ocean plan “to identify areas that have the least conflicts,” said Bruce Carlisle, director of the state Office of Coastal Zone Management. He cautioned that any sand mining would need to “be balanced with other interests” such as protecting fish habitat and maritime concerns.

Some coastal experts are calling for a regional approach: Find pockets of sand offshore that everyone could mine. While Winthrop’s offshore proposal became an environmental flashpoint, not every area needs to be.

“You could strategically select sand sources . . . and borrow appropriately to minimize environmental impact,’’ said Bob Hamilton, a coastal engineer and vice president of the Woods Hole Group in Falmouth, an environmental consulting firm.

Historically, much of the sand deposited on area beaches was a byproduct — material dredged to clear navigational channels.

But large-scale navigation projects by the Army Corps of Engineers are declining in New England. In Massachusetts, for example, there were about six projects per year in the early and mid-2000s, according to the Corps. Excluding Hurricane Sandy work, there have been none in the past three fiscal years, according to Ed O’Donnell, chief of navigation for the Corps New England District. The region, with few deep ports and relatively small amounts of cargo traffic, does not compete well against other regions in the country for navigational projects, he said. So when a navigation project is planned — as one is now in Eliot, Maine, to dredge the Piscataqua River — communities line up to get sand.

Some communities, such as in Barnstable County, banded together with the state’s help to buy a dredge that allows them to mine sand-clogged channels and inlets, providing sand that can be as much as 70 percent below the market rate. But other coastal communities do not have such options and must look elsewhere. Duxbury Beach Reservation Inc., a nonprofit group, spent more than $1 million this year rebuilding dunes with imported quarry sand.

“We are always looking for sand,’’ said Margaret Kearney, president of the group.

Fighting the sea

The fresh layered dunes and snow fencing in front of beach homes on Plum Island’s southern end belie the ragged erosion from this year’s February blizzard and March nor’easter. The storms toppled or forced the demolition of seven homes on the Newbury portion of the island.

The destruction intensified homeowners’ long fight with state officials for the right to save their properties.

Several homeowners were allowed by the state and Army Corps to take sand from the beach to place in front of homes last year right before Sandy, as an emergency measure. Yet state and federal officials rarely approve this measure, called beach scraping, because it can harm bird and other wildlife habitat and exacerbate erosion, because it changes a beach’s contours. Now, a larger group of homeowners is expected to apply this year for approval of beach scraping — setting up a possible showdown with regulators.

“We need to protect beaches,’’ said Bob Connors, a Plum Island resident whose Newbury beachfront house is threatened by the sea. The beach, he added, provides “protection for roadways and other structures behind them. If we want to have beaches in Massachusetts we have to sustain them — it’s just like painting a bridge.”

A few miles north on Salisbury Beach, Ray Champagne, head of the Salisbury Beach Betterment Association, agrees. Oceanfront owners spent upward of $5,000 each in the last year to re-create dunes in front of their homes that were washed away by last year’s storms. But the state beach in front of the homes remains low, raising fears that the ocean may come in even faster this nor’easter season and overcome their dunes and flood homes.

They want a $300,000 earmark — vetoed by Governor Deval Patrick but overridden by the Legislature — to be used to put sand on the state beach, in front of homes. So far, no decision has been made by the state about where to put the sand.

The New England Center for Investigative Reporting is a nonprofit investigative reporting newsroom based at Boston University and WGBH TV/radio and supported in part by New England news outlets. NECIR interns Michael Bottari and Alicia Juang helped research and prepare this report. Follow Beth Daley on Twitter at @BethBDaley.